Slime-Shooting 'Spiderman' Worm Snail Discovered on Sunken Shipwreck

It's exactly what it sounds like.
April 5, 2017, 11:00am
Rudiger Bieler/The Field Museum

"Cute" isn't a word that most would associate with giant slime glands. But to Dr. Rüdiger Bieler, the sight of a mucus-shooting, predatory sea snail was downright adorable.

Bieler, an invertebrates curator at Chicago's Field Museum, was exploring a shipwreck off the Florida Keys when he discovered a new species of worm snail.

L. Funkhouser

Rudiger Bieler diving

Thylacodes vandyensis has only been documented in a single location: on the USNS General Hoyt S. Vandenburg, a retired Navy vessel that was intentionally scuttled to create an artificial reef. (In 2003, Bieler and his colleagues similarly discovered Hyotissa hyotis, the giant honeycomb oyster, on another shipwreck in the area.) The snail's scientific name comes from "Vandy," which is the nickname that scuba divers bestowed the wreck.

The little mollusks are as diverse as they are weird-looking—resembling fusilli pasta, and generally found affixed to rocks or coral. And, sort of like Spiderman, they're capable of shooting sticky webs at unsuspecting prey.


According to Bieler, worm snails "have an extra pair of tentacles down near the base of their body, almost like little arms," which they "use to shoot slime."

But unlike Spiderman, worm snails use their webs to feed on microorganisms that become trapped and eventually hoisted back into their mouths. Since these animals are stationary—remaining in one spot for their entire lives—an adaptation is necessary for the worm snail's survival. They're "kind of cute," he added.

Bieler believes that T. vandyensis could be invasive, or non-native, to the Florida Keys. This also means the species currently exists, undiscovered, somewhere else, but researchers aren't exactly sure where. Worm snails can be especially destructive in non-native habitats. They've been found burrowing into coral, and can play host to blood flukes, which are marine parasites that feed on threatened loggerhead turtles.

Kate Golembiewski/The Field Museum

Worm snail holotype

"Eradication of clearly recognized invasive species is certainly a possible approach, and would require the appropriate permits from the National Marine Sanctuary that administers the area," Bieler told me.

"We will first want to figure out where they are coming from. They are new to science and very likely non-native—but what it their natural source region?"

For now, Bieler hopes his discovery will help other invertebrate researchers to better understand existing collections. His findings were published today in the journal PeerJ, along with colleagues from Florida International University and Cape Breton University.